Acute blockage of vessels of the mesentery of the intestine: causes, symptoms, treatment

Acute blockage of vessels of the mesentery of the intestine (in the language of medical terminology – acute occlusion of the mesenteric vessels) is the acute onset of a violation of blood flow in the vessels of the mesentery, which leads to the deterioration of food of the intestinal wall and develop in her various pathological processes.

Mesentery – a thin film of connective tissue, which attaches the intestines to the abdominal wall and which pass blood vessels and nerves.

Therefore, occlusion of mesenteric vessels may lead to serious violations on the part of the small intestine and colon throughout

General data

Acute blockage of the mesenteric vessels is considered urgent pathology in gastroenterology. But in fact it involved in the surgical hospital, as a circulatory disorder of the intestine leads to its irreversible changes requiring surgical intervention.

The degree of intestinal injury in acute occlusion of the mesenteric vessels is dependent on factors such as:

• view blockage;
• the level in the blood vessel where it occurred;
• the presence of additional arterial routes, which can take over the function of supplier of blood in case of blockage of the other branches and to compensate for the lack of blood supply (called collateral pathways of blood flow).

Blockage of the vessels of the mesentery may be:

• blood;
• venous;
• mixed (arterio-venous).

In 90% of all clinical cases of occlusion of the mesenteric vessels is the blockage of the main trunk of one of the largest mesenteric artery – superior mesenteric – or its major branches. This artery plays a major role in the blood supply to the gastrointestinal tract. The inferior mesenteric artery can also be occluded, but it referred to well-developed collateral branches, so it is a blockage at any level is not so fraught.

Mesenteric veins being clogged less often. Also not very frequent cases of the mixed occlusion of mesenteric (mesenteric) arteries and veins. Under mixed type of the first occlusion chronic occlusion of one vessel, and on its background – an acute obstruction of the other.

Most often this pathology is observed in men. Mostly it is diagnosed at the age of 50 years.

Reasons

Acute blockage of vessels of the mesentery of the intestine can be caused by:

• the clot is compacted blood clot;
• embolus – any biological substrate that is in the vessel lumen and not associated with them and can easily migrate from the blood.

In most clinical cases of mesenteric vessels clogged by a blood clot.

Pathology rarely occurs due to the formation of a clot directly in the vessels of the mesentery. The bulk of her precede cardiovascular disease, due to which the formation of blood clots, migrating then to the mesenteric vessels, although there may be nanosuite causes occlusion of the mesenteric arteries and veins.

Most often it occurs in such diseases and conditions as:

• atherosclerosis – the formation of fatty plaques on the inner surface of the vessel;
• heart disease – the changing anatomy of the Atria and ventricles of the heart;
• systemic allergic vasculitis – lesions of the internal surface of the vascular wall due to increased sensitization (sensitivity) of the organism;
• rheumatic fever – systemic inflammatory disease affecting connective tissue, which, in addition to the joints, affects the heart and with all the consequences;
• hypertension;
• aortic aneurysm – bulging of the wall of the vessel in the form of a bag (most often observed aneurysm of the abdominal aorta);
• arrhythmia;
• diseases associated with increased clotting of the blood;
• heart surgery;
• surgical correction of the pathology of the aorta;
• malignant neoplasms;
• injury, accompanied by bleeding and accompanying thrombosis.

As embolus may be:

• air bubbles;
• adipose tissue of the body (fractures of tubular bones);
• oil solutions, accidentally introduced into the blood stream;
• fragments of tumor tissue;
• foreign bodies (e.g. small fragments entering the bloodstream for gunshot wound);
• conglomerates of microbes;
• parasites;
• fluid (amniotic fluid).

The development of the disease

Once blood flow in the mesenteric vessel clot or embolus block its lumen.

Often a blood clot, which subsequently lead to blockage of the vessel, preceded by the so-called triad Vihrova:

• the change of the vessel walls;
• increased blood clotting;
• local (local) slowing of blood flow.

In some cases, even a small clot or embolus freely migrated in the vascular system with blood flow, may at any time to occlude the vessel, turning it.

Acute blockage of the mesenteric vessels of the bowel sharply resultant disruption of blood flow. It develops in vascular sites above and below the blocked area. In response to the irritation of the inner lining of the vessel, which “rested” on the edge of a thrombus or embolus, vessel reacts with spasms, which further exacerbates the obstruction to the blood in this part of the vascular system. Another aggravating factor is the additional thrombus formation at the place of blockage. As a result of all these pathological processes is terminated the flow of oxygen and nutrients to the tissues of the intestine, develops an acute disturbance of its nutrition, and ischemia (oxygen starvation) of the intestinal wall.

If not taken any measures for the resumption of the blood flow or if the clot (an embolus) will not spontaneously slip out of the narrow space of the vessel, will soon develop destructive (destructive) changes in the tissues of the intestines, which are provided with blood through this vessel. Such changes are irreversible.

The most severe consequences of acute occlusion of mesenteric vessels – anemia (AZ disorders of blood flow) and hemorrhagic (due to small hemorrhages) necrosis of the intestinal wall. Therefore, for occlusion of the mesenteric vessels is characterized by an extremely severe course and high mortality rate.

Acute blockage of the mesenteric vessels of the bowel can occur in three forms – compensation, decompensation subcompensation and mesenteric blood flow.

The difference between them is the following:

• in compensation the intestinal wall suffers from intermittent fasting, but then anatomically and functionally restored. This can occur spontaneously or by conservative treatment;
• when subcompensation observed robbing mesenteric blood flow, tissue bowel krovosnabjaemah partially and receive less nutrients, which leads to the development of a number of intestinal diseases, but often non-fatal and treatable. When subcompensation mesenteric blood flow may experience abdominal toad (oxygen starvation of the intestine, leading to the deterioration of its functions), enteritis (inflammation of the small intestine), colitis (inflammation of the mucous membrane of the large intestine), including peptic ulcer and some other diseases;
• when decompensated mesenteric blood flow practically stops, which leads to necrosis of the intestinal wall, and the accession of infection, the development of diffuse peritonitis and occurrence of severe septic conditions with the threat of death.

Symptoms

Acute blockage of the mesenteric vessels can occur immediately – it may be preceded by the so-called harbingers of disease (a similar principle – the manifestation of precursors during the preinfarction condition, if disturbed blood flow in the vessels of the heart). It depends on the degree of circulatory disorders. These symptoms precursor called abdominal toad is:

Characteristics of pain associated with abdominal toad:

• localization often starts in the navel region and then spread throughout the abdomen, although it may begin to hurt all of the stomach;
• by the force of varying intensity, mostly alternating medium and severe degree of gravity;
• in nature – in the form of spasms and cramps;
• at the time of occurrence – most often observed after a meal.

Such signs should cause medical concern, as there is a risk of occurrence of acute occlusion of the mesenteric vessels of the bowel.

But in most cases, the blockage of blood vessels of the mesentery begins suddenly, without precursors. Its clinical manifestations depend on the stage of the disease. There are three sequentially developing stages of occlusion of the mesenteric vessels of the bowel:

Stage of ischemia develops in the first 6-12 hours after the occlusion. Its clinical manifestations are the following:

• unbearable abdominal pain in the form of strong contractions. The patient can not sit still, trying to alleviate their condition and for this purpose adopts an emergency position – curled in the “fetal position” and leads the feet to the abdomen;
• severe nausea almost immediately joined by vomiting. First in the vomit can be detected in the bile and streaks of blood (hereinafter blood clots). With the progression of the disease vomit have fecal odor;
• frequent liquid stool, which detect the admixture of blood. This chair is also called ischemic (coming from oxygen starvation) bowel movement.

Stage of infarction developed in the period of time 12-18 hours of blockage. Its clinical manifestations are the following:

• pain felt at rest, in some measure subside, but increased tenderness at palpation of the abdomen;
• the General condition of the patient deteriorates;
• manifestations of diarrhea reduced, the chair is partially normalized.

The stage of peritonitis, occurs within 18-36 hours of the blockage. Its clinical manifestations are the following:

• buildup of abdominal pain. They are especially amplified when trying to walk;
• the sharp deterioration of the General condition of the patient, in particular due to intoxication (poisoning organism products of disintegration of the ischemic intestinal wall);
• gases do not depart;
• the patient does not defecate.

Diagnosis

Symptoms in acute blockage of the mesenteric vessels is quite pronounced, particularly helpful in the diagnosis of observation of the change in complaints. Also important are the details of history (of diseases) as acute onset of abdominal pain and the patient’s cardiovascular disease. To confirm the diagnosis using physical (inspection, palpation, percussion, auscultation of the abdomen), instrumental and laboratory methods of diagnosis.

In the stage of ischemia of the data of physical examination are as follows:

• during the inspection revealed a sharp pallor of integuments and visible mucous membranes, and then cyanosis (bluish tint), tongue dry, coated with white bloom. Abdominal wall takes part in breathing, which is a typical phenomenon in the conditions of the categories of acute abdomen;
• palpation (feeling) of the abdomen also revealed a discrepancy of results General condition during the first hours the abdomen is soft, tenderness is negligible. The symptoms of peritoneal irritation are absent.
• percussion (tapping) of the abdomen, significant changes are not detected;
• auscultation of the abdomen (listening with a stethoscope), there is increased intestinal noise.

Observed changes in the cardiovascular system:

• increase in blood pressure on average 60-80 units (so-called symptom Blinova);
• the pulse becomes more rare than normal.

In the stage of the heart attack data of physical examination are as follows:

• during the inspection there has been a further deterioration of the General condition of the patient;
• palpation in the place where is projected affected the gut, increasing the pain. You can also find oblong cylindrical raised, tender education with a doughy consistency;
• with percussion there is pain in the affected area;
• auscultation and little change is observed.

Changes in the cardiovascular system of the following:

• blood pressure returns to normal performance;
• the heart racing.

In the stage of peritonitis data of physical examination are as follows:

• upon inspection of recorded serious condition of the patient. The skin is a pale earthy color, the language is very dry, lined white-dirty tinge, the belly of participation in the act of respiration does not accept;
• palpation – severe pain, anterior abdominal wall is tense (surgeons describe it: “as a Board”), clearly identified the symptoms of peritoneal irritation;
• percussion – severe pain even with a slight tap on the wall of the abdomen;
• auscultation peristaltic hums are absent due to the onset of paralytic ileus.

Changes in the cardiovascular system of the following:

• expressed arterial hypotonia;
• a marked acceleration of the pulse.

To clarify the location of the lesion and other parts used by such instrumental methods of diagnostics as:

• review fluoroscopy and -graphy of the abdominal cavity – when it is determined that the loop of the intestine is much swollen (the so-called pneumatization intestines) and the abdominal cavity, a fluid (effusion, which in this case is formed as a result of the development of peritonitis);
• selective mezenterialnah – selective (selective) study of the mesenteric vessels. By catheterization of the femoral or axillary veins in the mesenteric vessels injected dose of contrast, and make x-ray picture (angiogram), which examine the state of the mesenteric vessels is their tortuosity, fullness and so on. At an early stage of the disease the study allows to fix the lack of blood flow in the mesenteric arteries;
• magnetic resonance angiography of the mesenteric vessels – the principle is the same as in the previous method, only after the introduction of contrast vessels study not using rendermethod, and the slices obtained during the MRI;
• diagnostic laparoscopy – through a small hole in the abdominal wall into the abdominal cavity injected laparoscop and with its built in optical system to visually examine the condition of the vessels of the mesentery and the intestinal wall.

Of laboratory methods of examination in diagnosis of occlusion of the mesenteric vessels is the most informative are:

• General analysis of blood on the accession of the infection and necrosis of the intestinal wall, will show a significant increase in the number of leukocytes and erythrocyte sedimentation rate. Also, the number of platelets evaluate the risk of thrombosis;
• biochemical blood analysis – determine the amount of cholesterol in the blood, thereby receiving indirect ability to determine the state of the inner surface of blood vessels;
• coagulation – analyzing her data, estimate the properties of the blood coagulation system and the ability to thrombus formation.

Differential diagnosis of

Symptoms typical of acute occlusion of the mesenteric vessels, can be observed in other diseases, which need differential diagnosis of occlusion of mesenteric vessels. This is such pathologies as:

Treatment

When signs of acute inclusion mesenteric vessels of the bowel of a patient in the emergency order hospitalitynet in the surgical Department.

The basis of treatment of this pathology:

• conservative therapy;
• surgery.

The operation must be performed on an emergency basis. The goal of surgery the following:

• audit (examination and evaluation) of the mesentery to check the blood flow and bowel to assess its viability;
• elimination of the reasons which provoked the vascular obstruction;
• restoration of blood flow in mesenteric vessels;
• resection (removal) of necrotic sections of the bowel.

The resumption of blood flow (revascularization) in the mesenteric vessels performed by methods such as:

• removal of a thrombus (thrombectomy);
• removal of the embolus (embolectomy);
• grafting – the process of creating a vascular prosthesis of detours blood flow (prosthesis of the superior mesenteric artery). Performed in severe cases.

If the wall of the intestine develop gangrene, these areas of the intestine excised. Excision is performed with capture of healthy tissue of the intestine, because the appearance of the affected intestinal segment does not match the level of deterioration of blood flow (external changes can be delayed). In some cases, surgeons make the decision on re-laparotomy (after 24-48 hours) to monitor the condition of the intestine.

Conservative treatment begins at the stage of preparation of the patient for surgery, continued during and after surgery.

The basis of conservative therapy are such appointments as:

• antithrombotic drugs to prevent a recurrence of thromboembolism of mesenteric vessels;
• aggressive fluid therapy is to restore blood volume, improve tissue blood supply and tissue metabolism (metabolism), stabilization of the cardiovascular system, removing the patient from a painful shock;
• antibiotic therapy – to prevent the development of infectious complications, and if they have already developed for their relief;
• oxygen therapy – oxygen supply through a mask into the respiratory tract.

Prevention

To prevent the occurrence of acute occlusion of the mesenteric vessels of the bowel is possible, if timely to address the sources of thrombosis. First and foremost, this means detection and treatment of diseases such as:

Also required clinical suspicion in relation to the occlusion of vessels by emboli – in the first place:

• fat particles;
• fragments of tumor tissue;
• air bubbles;
• parasites;
• fluids.

Forecast

The prognosis of this disease complex. If we can restore blood flow in the mesenteric arteries during the first 4-6 hours after the onset of vascular occlusion, this makes it possible to avoid infarction of the bowel to resume normal operation.

As a rule, surgical treatment is carried out in the second and third stages of occlusion is mainly due to late presentation of patients and time required to carry out diagnostic activities. Due to the late care the mortality rate is 80-90%. The forecast is deteriorating due to the underlying pathology, which contributed to the formation of a thrombus and occlusion of mesenteric blood vessels to them.